Skip to main content
Neil ArmstrongSoftware architect and developer
Menu

Belfast · Northern Ireland

I’m Neil Armstrong, a software architect in Belfast. I build and rebuild critical systems without breaking them, and I prove it with tests anyone can read.

I’m a genuinely full stack developer. For more than a decade I’ve led teams across React front ends, AWS serverless, Java/Kotlin back ends, native Android, and 3D in the browser. I care as much about what people need from the software as how it’s built, and I use AI tools with a person accountable for every result.

Explore my software work Start a conversation (opens in a new tab)
Neil Armstrong, a software architect and developer in Belfast
Front end
React and TypeScript, including a rewrite of an application used every day by more than 200 loan officers.
Back end and cloud
Java services, then AWS serverless: a full insurance sign-up journey in twelve months.
Mobile and desktop
A native Android point-of-sale app in Kotlin, and Electron desktop tools with 3D rendering.

Professional work

Systems I’ve delivered

Anonymised case studies from client work, each with what I did and how I knew it worked.

  • 2025–2026

    Build it again, but better

    Rebuilding a critical loan-processing application and more than 50 Lambda functions, with acceptance tests as proof that nothing regressed.

    Read the case study

    TypeScript · React · Redux Toolkit · AWS Lambda · Terraform · Playwright · Acceptance testing

  • 2025

    Replacing a legacy document builder

    Replacing an end-of-life, plug-in-based editor for legal loan documents in a single summer, with a contract at stake.

    Read the case study

    React · TypeScript · XML parsing · Document editing · Performance tuning · Legacy modernisation

  • 2025–2026

    Getting a platform modernisation back on track

    Recovering two struggling teams on a time-critical PHP modernisation, with a walkable rough frontend and a proxy between the old API and the new services.

    Read the case study

    React · Next.js · SST · AWS Lambda · Incremental migration

See all software work →

Open source

Projects built in the open

Useful software in its own right, and a practical view of how I approach architecture and AI-native delivery.

Away from the desk

Pedals instead of pull requests

When I’m not at a keyboard, I’m usually on a bike. My favourite trip so far took me from Tokyo to Seoul: across Japan, a ferry to Korea, and on to the capital, with the photos, the numbers, and everything that went wrong.

2,304 km · 20 riding days · 10 chapters

Read Tokyo to Seoul All trips
A forested mountain valley with a reservoir under a partly cloudy sky

Open to conversations

Got a system nobody dares touch?

I’m open to conversations about modernising legacy systems, leading delivery teams, and building test-driven architecture.

Message me on LinkedIn (opens in a new tab)